Acondicionamiento del grano de amaranto (Amaranthus spp.) para la obtención de una harina hiperproteica mediante molienda diferencial

Differential milling, especially for the amaranth grain (Amaranthus spp.), makes flour with a protein content higher than 40% possible but requires a conditioning of the grain moisture content, adjusting the moisture gradient by means of a quick dehydration. The aim of this work was to determine the drying conditions that give the maximum performance of flour with a high protein content not less than 40% by means of a 2 3 experimental design with three central points, taking drying air temperature and drying time as independent variables. Tests were carried out on grains with 11.5% initial moisture. The most suitable conditions found were 90 °C and 3 minutes with 36.9% extraction performance of flour with 40.10% protein content, and 70 °C and 7 minutes with 7% lower performance than the previous one. As a consequence of the drying effect, the available lysine decreased 38.5 and 16.4%, respectively, with respect to the control sample. Differential milling outputs were compared with those obtained in other mills.